Endoscope and method of use

ABSTRACT

An endoscope includes a shaft having proximal and distal ends and a longitudinal axis therebetween. A handle is coupled to the proximal end of the shaft, and an image sensor is carried on the distal end of the shaft. A channel extends through at least a distal shaft portion and has a channel diameter, and a section of the channel is re-configurable between a constricted shape and a non-constricted shape to accommodate tools introduced therethrough. The combined diagonal dimension and channel diameter is usually greater than the outer shaft diameter. The image sensor may be connected to a connector on the housing by a first slack flex circuit and a lights source on the shaft may be connected to a connector on the housing by a second slack flex circuit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a non-provisional application of U.S. provisionalapplication 62/723,393 filed Aug. 28, 2018, the entirety of which isincorporated by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates generally to medical devices and methods.More particularly, the present invention is related to endoscopicsystems suitable for hysterectomy and other purposes.

Endoscopic systems of the invention intended for hysterectomy typicallycomprise a base station having an image display, a disposable endoscopecomponent with an image sensor, a re-usable handle component that isconnected to an image processor in a base station, and a fluidmanagement system integrated with the base station and handle component.The endoscope component and the re-useable handle are typically referredto as a hysteroscope.

Of particular interest to the present invention, hysteroscopes and otherendoscopes provide for the introduction of interventional tools througha working channel in the shaft of the scope. The size of the workingchannel of a hysteroscope is limited by the need to introduce at least adistal portion of the shaft through the patient's cervix.

Of further interest to the present invention, hysteroscopes may have ashaft rotatable relative to the handle, and that shaft will often carrya camera and light source that need to be externally connected throughthe handle.

Of still further interest to the present invention, rotatablehysteroscope shafts may also carry fluids through a lumen, which has anexternal port fixed in the handle.

For these reasons, it would be desirable to provide improvedhysteroscopes, which can accommodate the introduction of comparativelylarge tools through a shaft with a relatively low profile. It would befurther desirable to provide improved hysteroscopes, which canaccommodate the connection of cameras, light sources, and the like, onrotatable shafts through stationary handles. It would be still furtherdesirable to provide improved hysteroscopes, which can accommodate theflow of fluids through rotatable shafts coupled to stationary handles.At least some of these objectives will be met by the inventionsdescribed hereinbelow.

2. Description of the Background Art

Hysteroscopic systems of a type similar to that illustrated herein aredescribed in commonly owned, co-pending application Ser. Nos.15/712,603; 15/836,460; 15/861,474; and Ser. No. 15/975,626, the fulldisclosures of which are incorporated herein by reference.

SUMMARY OF THE INVENTION

In a first aspect of the present invention, a hysteroscope or otherendoscopic system comprises a shaft having an outer shaft diameter, adistal shaft portion, a proximal shaft portion, and a longitudinal axistherebetween. A handle is coupled to the proximal portion of the shaft,and an image sensor with a diagonal dimension is carried by the distalportion of the shaft. A channel extends through at least the distalshaft portion and has a channel diameter. A section of the channel inthe distal portion of the shaft is re-configurable between a constrictedshape or geometry and a non-constricted shape or geometry to accommodatea tool introduced therethrough. Because of the re-configurable nature ofthe distal portion of the channel, the combined diagonal dimension andchannel diameter may be greater than the outer shaft diameter. Thehandle will typically be detachably coupled to the shaft so that thehandle is reusable and the shaft is disposable, but at least someaspects of the present invention will be found in endoscopes comprisingfixed handle-shaft structures as well.

In certain exemplary embodiments of the endoscopes of the presentinvention, the diagonal dimension will be at least 50% of the outershaft diameter, typically being at least 60%, or greater. In furtherexemplary embodiments, the channel diameter will also be at least 50% ofthe outer shaft diameter, more often being at least 60% of the outershaft diameter, or greater.

In other exemplary embodiments, the endoscopes of the present inventionwill be provided in systems, which further comprise a fluid inflowsource for providing fluid flow through an inflow channel in the shaftto an outlet in the distal portion of the shaft. Usually, such systemswill further comprise a negative pressure source for providing fluidoutflows through the outflow channel in the shaft and an opening in thedistal shaft portion. Still further, the systems may comprise acontroller for controlling fluid flows through the inflow and outflowchannels and at least one actuator in the handle for adjusting fluidinflows and outflows. For example, the controller may be configured withalgorithms for operating the fluid inflow source and the negativepressure source to maintain fluid within a set pressure range in aworking space, such as the uterine cavity.

In a second aspect of the present invention, a hysteroscope or otherendoscope comprises a handle having an interior, an axis, and anelectrical connector fixed to the handle. A shaft is removably orotherwise coupled to the handle and configured to rotate, typicallyreversibly rotate, about a longitudinal axis relative to the handlethrough an arc of about 180° or greater. An electronic image sensor iscarried at a distal end of the shaft, and one or more electrical leadsextend from the image sensor to the electrical connector in the handle.The electrical lead(s) are flexible and configured with a “slack”portion in the interior of the handle to accommodate rotation of theshaft. By “slack,” it is meant that the length of the electrical lead(s)is greater than the distance between the electrical connector and thepoint of attachment of the electrical lead(s) to the shaft so that theshaft may be rotated without over tensioning the electrical lead(s).

In further exemplary embodiments of this endoscope, the slack portionmay be formed as any one of a coil, a spiral, a folded structure, aserpentine structure, or the like. In specific embodiments, one end ofthe slack portion will be coupled to and extend around the axis of therotating shaft assembly, typically being carried on a spool secured tothe shaft assembly. The spool is usually aligned concentric orco-axially with the axis of the shaft so that as the shaft is rotated,the spool may take up or let out the flexible electrical leads asneeded. In specific examples, the electrical leads may comprise the flexcircuits.

In still further exemplary embodiments of these endoscopes, a lightemitter may be carried at the distal end of the shaft and secondelectrical lead(s) may extend from the light emitter to a secondelectrical connector fixed in the handle. The second electrical leadsare configured with a second slack portion to accommodate rotation ofthe shaft. The second shaft portion may also be carried on a secondspool and may comprise a flex circuit.

In still further aspects of this endoscope, a channel may be formed inthe shaft where a portion of the channel is re-configurable between aconstricted shape and a non-constricted shape to accommodateintroduction to a tool through the channel. As with the first endoscopicembodiments described above, the combined diagonal dimension and channeldiameter will typically be greater than an outer shaft diameter. Otherspecific aspects of the re-configurable channel described above withrespect to the earlier embodiment may also be found in the endoscopes ofthe second aspect herein.

In the third aspect of the present invention, an endoscope comprises ahandle and an elongated shaft. The elongated shaft is mounted to rotate,typically reversibly, at least 180° about a longitudinal axis of thehandle. An electronic image sensor is carried near a distal end of theshaft, and electrical leads extend from the image sensor to the handle.The electrical leads are configured to coil and uncoil (spool andunspool) over the shaft as the shaft is rotated in opposite directionsabout the longitudinal axis. In specific embodiments of this thirdendoscope structure, the electrical leads may comprise a flex circuitand at least a portion of the flex circuit may have a cross-sectionalarea that is less than 5% of the cross-sectional area of the shaftassembly.

In a fourth aspect of the present invention, an endoscope comprises ahandle in an elongated shaft mounted to rotate by at least 180° about alongitudinal axis of the handle. A flow channel extends through theshaft assembly to a port in a distal end of the shaft. The flow channelhas a proximal channel portion fixed in the handle and a distal channelportion that rotates together with the shaft. A fluid-tight housingintermediate the proximal and distal channel portions is configured toprovide a fluid-tight path through the channel portions within the fullrotational range of the shaft.

In specific aspects of the fourth endoscope of the present invention,the rotating shaft may include an annular flow channel that rotates inthe housing. The endoscope may still further include a second flowchannel extending through the handle and shaft assembly, where thesecond flow channel has a proximal channel portion fixed in the handlecomponent and a distal channel portion that rotates in the shaft as theflow channel rotates in the housing.

The present disclosure also includes a method for orienting an image ona display from an endoscope with an image sensor. For example, such amethod can include providing an endoscope having a longitudinal axis anda distal image sensor that provides an image on a display; providing atleast one of an accelerometer and gyroscope carried by the endoscope;and acquiring signals from the at least one of an accelerometer andgyroscope caused by rotation of the endoscope relative to thelongitudinal axis; rotating the image on the display in response to thesignals to correct the orientation to a selected configuration.

The selected configuration can comprise an image-upright configurationand wherein the rotating step comprises manipulating said imageelectronically.

In one variation of the method, wherein the accelerometer is locatedwithin a housing of the endoscope on a rotating component, the methodfurther comprising rotating the distal image sensor independently of ahandle of the endoscope and using the accelerometer to determinerotation of the distal image sensor independently of the handle.

The method can further comprise providing at least a secondaccelerometer carried on a handle of the endoscope, the method furthercomprising acquiring signals from the second accelerometer and comparingsignals from the at least one of the accelerometer and the secondaccelerometer.

Another variation of an endoscope comprises an endoscope that iselectrically coupled to an image display, the endoscope can include anelongated shaft having a housing located at a proximal end of theelongated shaft and an image sensor located at a distal end of theelongated shaft; a handle coupled to the housing of the elongate shaft;a first accelerometer and gyroscope within the housing and coupled tothe elongate shaft such that rotation of the elongate shaft rotates thefirst accelerometer, wherein the first accelerometer and gyroscope areconfigured to provide signals from the to determine rotation of theimage sensor relative to a longitudinal axis of the elongated shaft,wherein the signals permit rotation of an image on the image display.

A variation of the endoscope can include a second accelerometer locatedwithin the handle. wherein the image sensor in the insertion profile hasa 0 to 15 degree viewing angle relative to a central axis of theinsertion profile.

Endoscopes as described herein can further comprise a flex circuithaving a plurality of electrical conductors, which are configured totransmit power and image signals to and from the image sensor, the flexcircuit including outer dielectric layers that are configured to shieldthe plurality of electrical conductors from electrical interference.

Another variation of an endoscope includes an elongated shaft extendingabout a central axis to a distal end carrying an image sensor at adistal end of the elongated shaft; a distal segment adjacent to thedistal end of the elongated shaft, wherein the distal segment comprisesan elongated discontinuity that permits side portions of the elongatedshaft at the distal segment to flex outwardly when an elongated toolshaft is advanced through the working channel; a working channel withinthe elongated shaft and extending to the distal segment of the elongatedshaft; and a support sleeve located about a portion of the distalsegment, the support sleeve urges the side portions of the elongatedshaft inward upon removal of the elongated tool shaft.

The support sleeve can further comprise an elongated discontinuityextending along a length of the support sleeve.

A variation of the endoscope includes a flexible hinge located at anintermediate segment that is adjacent to the distal segment, whereininsertion of the elongated tool shaft causes the distal end of theelongated shaft to displace radially away from the central axis.

Another variation of the endoscope further comprises a housingconfigured to carry the image sensor and at least one light emittingdiode.

The endoscope can also include an upper guide surface coupled to thehousing, wherein advancement of the elongated tool shaft distally beyondthe working channel causes the elongated tool shaft to push against theupper guide surface to deflect the housing. Optionally, the endoscopecan further comprise a lower guide surface coupled to a sleeve of theworking channel, where the lower guide surface provides a slidinginterface against which the elongated tool shaft can advance through thedistal segment without contacting the support sleeve.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional aspects of the invention will become clear from the followingdescription of illustrative embodiments and from the attached drawings,in which:

FIG. 1 illustrates components of a hysteroscopic treatment systemcorresponding to the invention, including a perspective view of anendoscopic viewing system and a schematic view of a fluid managementsystem.

FIG. 2 is a perspective view of the endoscopic viewing system of FIG. 1, showing a single-use disposable endoscope component separated from areusable handle component.

FIG. 3A is a perspective view of the single-use endoscope component ofFIG. 2 with the handle shell partially removed to show an interiorportion of the component.

FIG. 3B is a perspective view of the endoscope component of FIG. 3A witha flow channel housing removed to show features of a rotating shaftassembly.

FIG. 4 is a perspective view of the endoscopic viewing system of FIG. 1from a different angle illustrating rotation of the rotating shaftassembly.

FIG. 5 is another perspective and sectional view of the endoscopecomponent of FIGS. 3A-3B with a flow channel housing removed to show thecentral axis of the working channel around which the shaft assemblyrotates and the off-center longitudinal axis of the outer sleeve of theendoscope shaft.

FIG. 6 is in an enlarged perspective view of the endoscopic viewingsystem of FIGS. 1 and 2 showing the finger-actuated control panel in thereusable handle component and the sterile and non-sterile fields of thecomponents.

FIG. 7A is an enlarged perspective view of the distal end of theendoscope shaft showing the working channel with a distal channelportion in a reduced cross-sectional configuration for introduction intoa patient's body.

FIG. 7B is another view of the distal end of the endoscope shaft of FIG.7A, showing the distal working channel portion in an expandedcross-sectional configuration when a tool is introduced through theworking channel.

FIG. 8 is another view of the distal end of the endoscope shaft assemblyof FIGS. 7A-7B showing the image sensor housing extending distally fromthe distal surface of the outer sleeve tip.

FIG. 9 is another view of the endoscope handle assembly, which carriesat least one accelerometer for image orientation.

FIG. 10 is a de-constructed view of the endoscope working end showing aflex circuit configuration.

FIG. 11 is another view of the endoscope working end of FIG. 10 .

FIG. 12A is another view of the endoscope working end of FIG. 11 in anon-articulated configuration.

FIG. 12B is another view of the endoscope working end of FIG. 11 in anarticulated configuration.

FIG. 13 is an exploded view of the components of the endoscope workingend of FIGS. 11, 12A and 12B.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates a hysteroscopic treatment system 50 corresponding tothe invention, which comprises multiple components including anendoscopic viewing system 100 and a fluid management system 105 housedin a base unit or console 108. The base unit 108 also carries acontroller 110A and power source for operating the system 50 and caninclude an image processor 110B for processing signals from an imagesensor carried by the endoscopic viewing system. A display 112 can becoupled to the base unit 108 for viewing images provided by theendoscopic viewing system 100.

More in particular, the endoscopic viewing system 100 of FIGS. 1 and 2includes a re-usable handle component 120 with a finger-actuated controlpad 122 and a disposable single-use endoscope component 125 with anelongated endoscope shaft 126 that carries a distal electronic imagingsensor 128 (see FIGS. 1 and 7A). The fluid management system 105includes a first peristaltic inflow pump 140A and second peristalticoutflow pump 140B, a fluid source 142 and fluid collection reservoir144, which can include a fluid deficit measurement subsystem as is knownin the art. Each of the systems and subsystems will be described in moredetail below.

Referring to FIGS. 1, 2 and 3B, it can be seen that the endoscopicviewing system 100 includes a handle component 120 and a detachablesingle-use endoscope component 125. In FIG. 2 , the single-use endoscopecomponent 125 can be seen as an assembly of a proximal handle housing145, which carries a rotating shaft assembly 150 that is configured torotate the handle housing 145.

Referring to FIGS. 1, 3B and 5 , the rotating shaft assembly 150includes a proximal cylindrical grip 152 that is coupled to a moldedrotating core 155 that in turn is coupled to elongated outer sleeve 160that extends to the distal working end 162 the endoscope component 125(FIG. 1 ). The rotating shaft assembly 150 rotates around a rotationalaxis 165. A working channel 170 extends about axis 165 through therotating shaft assembly 150 from a proximal port 172 (see FIGS. 2 and 6). The working channel sleeve 174 that carries the working channel 170can be seen in FIGS. 3A, 3B and 5 . Thus, the shaft assembly 150 rotatesabout the central longitudinal axis 165 of the working channel 170. Ascan be seen in FIGS. 5 and 7A, the outer sleeve 160 has a centrallongitudinal axis 175 that is offset from the longitudinal axis 165around which the shaft assembly 150 rotates. FIG. 4 shows that the grip152 has a visual marker 178 that is aligned with the offset distal tipsection 185 to allow the operator to know the orientation of the imagesensor 128 by observation of the grip 152.

In FIGS. 1, 4, 6 and 7A, it can be seen that the endoscope shaft 126 andmore particularly the outer sleeve 160 extends in a straight proximalsleeve portion 180 to an offset distal tip section 185 with an axis 182that is also from 2 to 10 mm offset from the central axis 175 of theouter sleeve 160 (FIG. 7A). The outer sleeve 160 has a transitionsection 186 that extends at an angle ranging between 10° and 45° over alength of 5 to 20 mm between the straight proximal sleeve section 180and the offset distal tip section 185. The imaging sensor 128 isdisposed at the distal end of the offset tip section 185 (see FIG. 7A).As can be seen in FIGS. 5 and 7B, the endoscope component 125 and morein particular the working channel 170 is adapted to receive an elongatetool 188 that can be introduced through the working channel 170. In onevariation, the elongated outer sleeve 160 in each of the straight,transition and distal tip sections (180, 186 and 185, respectively) hasa diameter ranging between 4 mm and 10 mm with an overall lengthconfigured for use in hysteroscopy. More commonly, the diameter ofendoscope shaft 126 is from 5 mm to 6 mm in diameter. It has been foundthat the endoscope shaft 126 with the angled transition section 186 andoffset distal tip section 185 can be introduced through a patient'scervical canal without dilation beyond the dilation necessary for theprofile or diameter SD of the straight proximal sleeve section 180. Inother words, the tissue around the patient's cervical canal conforms tothe angles in the endoscope shaft 126 as the shaft is being advancedthrough the cervical canal.

In one variation, the handle housing 145 of endoscope component 125 isadapted for sliding, detachable engagement with the handle component 120as can be best seen in FIGS. 2 and 4 . As can be easily understood, whenassembled, the operator can grip the pistol grip handle component 120with one hand and rotate the cylindrical rotating grip 152 with thefingers of the other hand to rotate the endoscope shaft and image sensor128 to orient the viewing angle of the image sensor 128 and a tool 188to any desired rotational angle. As will be described below, therotating shaft assembly 150 can be rotated at least 180° and more oftenat least 270° (FIGS. 3B and 5 ). In one variation, the shaft assembly150 can be rotated 360° so as to orient the image sensor 128 in anysuperior, lateral or downward direction relative to the handle housing145.

As can be seen in FIG. 2 , the handle housing 145 carries a projectingelectrical connector 190A that is adapted to couple to a matingelectrical connector 190B in the handle component 120. While FIG. 2illustrates that the endoscope component 125 is configured for axialsliding engagement with the handle component 120, it should beappreciated that the angled pistol grip portion 192 of the handlecomponent 120 could plug into the endoscope component 125 in a differentarrangement, such as a male-female plug connector or a threadedconnector aligned with the axis 194 of the angled grip portion 192. Aswill be described below, the endoscope component 125 comprises a steriledevice for use in the sterile field, while the handle component 120 maynot be sterilized and is typically adapted for use in a non-sterilefield. A cable 195 extends from the handle component 120 to the baseunit 108, imaging processor 110B and controller 110A, which includes apower source (see FIG. 1 ).

As can be seen in FIGS. 1 and 2 , the endoscope component 125 includesfluid inflow tubing 200A and fluid outflow tubing 200B that communicatewith the fluid management system 105, which is shown schematically inFIG. 1 . As can be understood from FIGS. 2, 3A and 3B, the endoscopehandle housing 145 can consist of two injection molded plastic shellelements, 204 a and 204 b (see FIG. 4 ), and FIG. 3A shows one shellelement 204 a removed to show the interior of the handle housing 145. Itcan be seen that both the inflow tubing 200A and outflow tubing 200B arecoupled to an injection molded flow channel housing 205 with an interiorbore 208 that is configured to receive a rotating core 155 of therotating shaft assembly 150.

FIG. 3B is another view similar to that of FIG. 3A with the second shellelement 204 b removed and the flow channel housing 205 also removed(phantom view) to illustrate how the stationary inflow and outflowtubing, 200A and 200B, communicate with the inflow and outflow pathwaysin the rotating shaft assembly 150, which rotates at least 180°.

Referring to FIGS. 3A and 3B, it can be seen that the rotating core 155is centrally aligned with the axis 165 of working channel 170 and isfurther coupled to the off-center elongated outer sleeve 160 of theendoscope shaft 126. The proximal end 212 of the rotating core 155 isfixed to the grip 152 for rotating the rotating core 155 in the flowchannel housing 205.

The rotating core 155 includes first, second and third flanges 218 a,218 b and 218 c, which define annular flow channels 220 and 222therebetween. It can be seen that annular channel 220 is disposedbetween the first and second flanges 218 a and 218 b. Annular channel222 is disposed between the second and third flanges 218 b and 218 c.Each of the first, second and third flanges 218 a, 218 b and 218 c carryan outer O-ring 224 a, 224 b and 224 c. From the views of FIGS. 3A and3B, it can be understood how the rotating flanges 218 a-218 c rotate inthe bore 208 of the flow channel housing 205 and the O-rings 224 a-224 cmaintain a fluid-tight seal between the annular flow channels 220 and222.

Again referring FIGS. 3A and 3B, it can be seen that the distal end 230a of inflow tubing 200A is fixed in the flow channel housing 205 tocommunicate with annular flow channel 222. Similarly, the distal end 230b of outflow tubing 200B is fixed in the flow channel housing 205 tocommunicate with annular flow channel 220. Thus, each of the annularflow channels 222 and 220 can rotate up to 360° and communicate with thestationary distal ends of the inflow tubing 200A and outflow tubing200B.

FIG. 3B further shows how the annular flow channels 222 in 220communicate with separate flow pathways that extend through the interiorof the elongated sleeve 160 to the working end 162 of the endoscopeshaft 126. The fluid inflow pathway can be seen in FIG. 3B, whichextends through annular gaps AG around the exterior of inner sleeveportion 235 of the rotating core 155 within the second annular channel222. Such annular gaps AG extend distally to communicate with theinterior bore 242 of the outer sleeve 160. In one variation, the pathwaywithin said interior bore 242 transitions to the inflow sleeve 244 withdistal outlet 245 as shown in FIGS. 7A-7B.

The fluid outflow pathway also can be seen in FIG. 3B wherein an opening250 is provided in the inner surface of annular space 220 of therotating core 155, which communicates with the interior working channel170. Thus, the outflow pathway from a working space in one variationcomprises the working channel 170, which is fully open for fluidoutflows when there is no tool 188 in the working channel. In FIG. 5 ,it can be seen that a tool seal 252 is shown in the proximal region ofthe working channel 170 that seals the channel 170 and also permits thetool 188 to be introduced therethrough. Many types of seals are known inthe art as silicone sleeve seals, flap seals and the like. Typically,when a tool is introduced through the working channel 170, the toolitself will provide an outflow channel. Thus, the use of the workingchannel 170 as outflow passageway is adapted for diagnostic procedureswhen using the endoscope without a tool in the working channel.

In a method of use, the endoscope shaft 126 can be navigated through apatient's end cervical canal with the inflow and outflow pumps 140A and140B (see FIG. 1 ) operating to provide continuous irrigation throughthe distal tip section 185 of the endoscope component 125 together withendoscopic viewing by means of image sensor 128. Such a variation willthus allow fluid inflows through annular channel 222 and fluid outflowsthrough the working channel 170 and annular channel 220.

Now turning to FIGS. 7A-7B, the endoscope shaft 126 has a smallinsertion profile or configuration that consists of the outer diameterof the elongated outer sleeve 160, which includes the proximal straightsection 180, the angled transition section 186 and the distal tipsection 185 (FIG. 7A). It can be seen in FIG. 7A that the distal tipsection 185 carries an image sensor 128 and two LEDs 260, which requirean electrical connection to base unit 108, the controller 110A andimaging processor 110B. In order to provide the large number ofelectrical leads required for the image sensor 128, it was found thatconventional multi-wire electrical cables were too large to beaccommodated by the small diameter outer sleeve 160 which alsoaccommodates working channel 170, an inflow channel 244 and potentiallyother fluid flow channels. For this reason, it was found that a printedflex circuit in the form of a flat ribbon 265 (FIG. 5 ) could providefrom 10 to 40 electrical leads and occupy only a thin planar spacewithin the endoscope shaft 126. FIG. 7A shows the flex circuit ribbon265 extending from the image sensor 128 proximally within outer sleeve160. In one variation shown in FIGS. 3A, 3B, 5 and 7A, a second flexcircuit ribbon 270 is provided to power the LEDs 260. In anothervariation, the first flex circuit ribbon 265 could potentially carryelectrical leads to the image sensor 128 and to the two LEDs 260.

Now turning to FIGS. 3A, 3B and 5 , mechanisms are illustrated thatprovide for needed slack in the electrical circuitry or flex circuitribbons 265 and 270 for accommodating rotation of the rotating shaftassembly 150 relative to the handle housing 145 (FIG. 3A). As can bestbe seen in FIGS. 3B and 5 , the rotating shaft assembly 150 includes afirst or distal spool 280 around which the flex circuit ribbon 265 canbe coiled or spooled. The distal spool 280 is formed as a part of therotating core 155 of the rotating shaft assembly 150. Any suitablelength of the flex circuit ribbon 265 can be provided as needed to allowfor at least 180° rotation, or more often, 360° of rotation of therotating shaft assembly 150 relative to the handle housing 145. In thevariation shown in FIGS. 3B and 5 , it can be seen that a second orproximal spool 285 comprises a portion of the rotating core 155 and isadapted for receiving a slack length of the second flex circuit ribbon270 that extends to the two LEDs 260. In FIGS. 3B and 5 , it can be seenthat the proximal ends 265′, 270′ of the flex circuit ribbons 265, 270are coupled to electrical connector 190A by plug connector 288 a and 288b. While the variation of FIGS. 3A-3B shows the endoscope handleaccommodating the flex circuit ribbon 265 in a spool 280, it should beappreciated that the slack portion of the flex circuit ribbon can beconfigured with at least one of a coiled form, spiral form or foldedform without a spool.

In one aspect of the invention, referring to FIG. 7A, an endoscope shaft126 is provided that carries a distal image sensor 128 wherein thediameter of a working channel 170 in the shaft 126 is greater than 50%of the outer diameter of the shaft 126 and the electrical leads to theimage sensor 128 comprise the flex circuit 265. In such a variation, theflex circuit ribbon has a thickness of less than 0.4 mm and a width ofless than 5.0 mm. More often, the flex circuit ribbon has a thickness ofless than 0.3 mm and a width of less than 4.0 mm. Further, in thisvariation, the flex circuit ribbon carries at least 10 electrical leadsof often more than 15 electrical leads. In another aspect, electricalleads extending to the image sensor 128 are in a cable or ribbon thathas a cross-section that is less than 5% or the cross-section of theendoscope shaft 126. In another aspect of the invention, the endoscopecomprises a shaft carrying a distal image sensor, a working channelextending through the shaft wherein the working channel in a distalshaft portion is re-configurable between a constricted shape and anon-constricted shape to accommodate a tool introduced therethrough,wherein the combined diagonal dimension DD of the sensor and thediameter WCD of the working channel 170 is greater than the shaftdiameter SD in its insertion configuration or profile (see FIGS. 4, 6and 7A).

In a specific example, the image sensor 128 is available fromOmniVision, 4275 Burton Drive, Santa Clara, Calif. 95054 with the partname/number: High Definition Sensor OV9734 with a 1280×720 pixel count.The sensor 128 has package dimensions of 2532 μm×1722 μm, with adiagonal DD of 3062 μm or 3 mm. Further, the proximal shaft (outer)diameter SD is 5 mm with the working channel diameter WCD being 3 mm.Thus, the combined sensor diagonal DD (3 mm) and the working channeldiameter WCD (3 mm) equals 6 mm, which is greater than the outer shaftdiameter of 5 mm. In this example, the flex circuit ribbon is 3.4 mm inwidth and 0.2 mm thickness with a cross-sectional area of 0.68 mm²,which is 3.52% of the 5 mm diameter shaft having a cross-sectional areaof 19.63 mm². In this specific variation, the flex circuit ribbon 265carries 19 electrical leads.

Referring again to FIGS. 7A-7B, the distal portion of the endoscopeshaft 126 includes a distal working channel portion 170′ that isre-configurable between a first smaller cross-section as shown in FIG.7A for accommodating fluid outflows and a second larger cross-section asshown in FIG. 7B for accommodating a tool 188 introduced through theworking channel 170 and its distal portion 170′.

In one variation, as shown in FIGS. 3A-3B, 5, 6, and 7A, it can be seenthat the working channel sleeve 174 that defines working channel 170extends in a straight configuration through the endoscope component 125from its proximal opening port 172 to its open distal termination 290.As can be seen in FIGS. 7A and 7B, the distal end 292 of sleeve 174 hasa superior surface 294 that is straight and rigid. The working channelsleeve 174 has an inferior or lower sleeve portion 296 that is flexibleand in one variation has a living hinge portion 298 below sidewallcut-outs 302 a and 302 b in the sleeve 174. Further, the distal end ofthe endoscope shaft 126 includes an elastomeric sleeve 310 thatsurrounds the angled transition sleeve section 186, the distal tipsection 185 as well as a distal portion 312 of the proximal straightsleeve section 180 (FIG. 7B). Thus, as can be seen in FIG. 7A, theelastomeric sleeve 310 has sufficient elastic strength to collapse orconstrict the working channel portion 170′ to the smaller cross-sectionas seen in FIG. 7A.

As can be seen in FIG. 7A, the lower sleeve portion 296 includes asleeve wall 315 with sufficient curvature to maintain an open pathwaythrough the distal working channel portion 170′ when the elastomericsleeve 310 constricts the distal channel portion 170′, which therebyalways provides an open fluid outflow pathway. For example, the sleevewall 315 can have a curvature representing the same diameter as aproximal portion of sleeve 174 and extend over a radial angle rangingfrom 30° to 90°. While the lower sleeve portion 296 shown in FIG. 7Acomprises a portion of the wall of metal sleeve 174, in anothervariation, the flexible lower sleeve portion 296 may be any bendableplastic material or a combination of plastic and metal.

FIG. 7B next shows the distal working channel portion 170′ in its secondexpanded configuration as when a physician inserts an elongated tool 188(phantom view) through the working channel 170. Such a tool 188 willinitially slide along the hinge portion 298 of the lower sleeve portion296 and then stretch the elastomeric sleeve 310 to open distal workingchannel portion 170′ to allow the tool 188 to extend through the workingchannel. In other words, the elastomeric sleeve 310 will be stretched ordeformed to a tensioned position as shown in FIG. 7B as a tool isinserted through the distal working channel portion 170′. When the tool188 is withdrawn from the working channel portion 170′, the elastomericsleeve 310 will return from the tensioned position of FIG. 7B to therepose or non-tensioned position of FIG. 7A to return the workingchannel portion 170′ to the constricted configuration FIG. 7A.

In general, the endoscope component 125 corresponding to the inventionallows for the use of an image sensor 128 having a large diagonaldimension relative to the insertion profile or diameter of the endoscopeshaft 126 while at the same time providing a working channel 170 thathas a large working channel diameter WCD relative to the insertionprofile or diameter of the endoscope shaft assembly 126. More inparticular, the endoscope component 125 comprises endoscope shaft 126having a shaft diameter SD extending to a distal sleeve section 185, animage sensor 128 with a diagonal dimension DD carried by the distalsleeve section 185 and a working channel 170 having a diameter WCDextending through the elongated shaft 126, wherein the working channelportion 170′ in the distal end of the shaft 126 is adjustable in shapeto accommodate a tool 188 introduced therethrough and wherein thecombination or the sensor's diagonal dimension DD and the workingchannel diameter WCD is greater than the shaft diameter SD (see FIG.7A).

In a variation, the sensor diagonal dimension DD is greater than 50% ofthe shaft diameter SD or greater than 60% of the shaft diameter. In avariation, the working channel diameter WCD is greater than 30% of theshaft diameter, greater than 40% of the shaft diameter or greater than50% of the shaft diameter. In other words, the working channel portion170′ in the distal end is adjustable between a first cross-sectionaldimension and a second cross-section dimension. In the variation ofFIGS. 7A-7B, the working channel portion 170′ in the distal region ofthe endoscope shaft 126 is adjustable between a partially constrictedshape and a non-constricted shape.

In one variation, referring to FIG. 7A, the distal tip section 185 ofthe endoscope shaft 126 has an axial dimension D1 ranging from 5 mm to20 mm. Also referring to FIG. 7A, the angled transition sleeve section186 extends over a similar axial dimension D2 ranging from 5 mm to 20mm. Still referring to FIG. 7A, the central axis 182 of distal tipsection 185 can be parallel to and offset from the longitudinal axis 175of the straight shaft section 180 by a distance ranging from 1 mm to 10mm.

Now turning to FIG. 8 , the image sensor 128 is carried in a sensorhousing 340 that also carries a lens assembly 345 as is known in theart. In one variation, the housing 340 also carries one or more lightemitters, in the variation shown in FIGS. 7A and 7B, two LEDs indicatedat 260 are shown carried in opposing sides of the sensor housing 340. Ofparticular interest, the distalmost surface 350 of the lens assembly 345and the LEDs 260 are disposed distally outward from the distal surface352 of distal tip section 185 as shown in FIG. 8 . It has been foundthat providing such a distalmost surface 350 of the lens assembly andthe LEDs outwardly from the distal surface 352 of distal tip section 185improves lighting from the LEDs 260 as well as improving the field ofview of the image sensor 128. The distance indicated at D3 in FIG. 7 canrange from 0.2 mm to 2.0 mm.

Now referring to FIG. 7A, another aspect of the invention comprises anoptional dedicated fluid pressure sensing channel 360 that extendsthrough a thin wall sleeve (not shown) in the endoscope shaft 126. Ascan be seen in FIG. 7A, the distal end of the pressure sensing channel360 is open in the distal surface 352 of the endoscope shaft 126. Thepressure sensing channel 360 can extend to disposable pressure sensor inthe handle housing 145 (not shown). Such a disposable pressure sensorthen can have electrical leads coupled through the electrical connector190A in the handle housing 145 thereby send electrical signalsindicating pressure to the controller 110A (FIG. 1 ). Thus, in oneaspect, the disposable endoscope component 125 carries a single-usepressure sensor coupled by a detachable connector to a remote controller110A.

In one variation of a pressure sensing mechanism, referring to FIG. 7A,the wall of the pressure sensing channel 360 consists of a hydrophobicmaterial, which can be any suitable polymer such as PFTE, having aninterior diameter ranging from 0.25 mm to 2.5 mm. Often, the diameter ofchannel 360 is between 0.5 mm and 1.5 mm. It has been found that ahydrophobic surface in a pressure sensing channel 360 will prevent themigration of fluid into the channel and thereby trap an air column inthe channel communicating with the pressure sensor. The compressibilityof the air column in the pressure sensing channel 360 is notsignificantly affected by the sensed pressure since the channel diameteris very small. In another variation, a metal sleeve can be coated with ahydrophobic surface or an ultrahydrophobic surface.

Now referring to FIGS. 1, 2 and 4 , it can be seen that the handlecomponent 120 has an angled pistol grip portion 192 with an axis 194that is angled from 10° to 90° away from the axis 175 of the endoscopeshaft 126. The grip portion 192 includes a finger or thumb-actuatedcontrol pad 122 that carries actuator buttons for operating all thefunctions of the treatment system, for example, including (i) operatingthe fluid management system 105, (ii) capturing images or videos fromsensor 128, (iii) adjusting light intensity from the LEDs 260, etc. Asdescribed above, the control unit 108 typically carries the imageprocessor 110B. However, the interior of the handle component 120 alsocould carry the image processor 110B or a processing component thereof.

FIG. 4 illustrated the handle component 120 and endoscope component 125from a different angle where it can be seen that the grip portion 192has a recessed channel 385 therein that is adapted to receive and lockin place the inflow and outflow tubing, 200A and 200B, so as tointegrate the tubing set with the pistol grip 192 during use. Thisfeature is important so that the inflow and outflow tubing will notinterfere with operation of the endoscope component 125 or a toolintroduced through the working channel 170. The pistol grip 192 can havea single recessed channel 385 to receive both the inflow and outflowtubing or two recessed channels for separately receiving the inflowtubing and the outflow tubing.

Now turning to FIG. 6 , the enlarged view of the assembled handlecomponent 120 and endoscope component 125 shows the control pad 122 withfour actuator buttons or switches, which are adapted to operate thesystem. In one variation, actuator 402 is adapted for turning on and offirrigation, or in other words actuating the fluid management system 105to provide fluid inflow and fluid outflows. Actuator 404 is adapted forimage or video capture. In a variation, momentary pressing the actuator404 will capture a single image and longer pressure on the actuator willoperate a video recording.

The actuator or scrolling button 406 has a scrolling function, whereinpressing the scrolling button 406 will cycle through various subsystems,wherein each subsystem then can be further adjusted by the centralbutton or up/down actuator 410, which is adapted for increasing,decreasing or otherwise changing an operating parameter of any selectedsubsystem. In one example, the scrolling button 406 can be actuated tocycle through the following subsystems and features: (i) fluidinflow/outflow rate from the fluid management system 105; (ii) the setpressure, which is to be maintained by fluid management system 105;(iii) fluid deficit alarm, which is calculated by the fluid managementsystem 105; (iv) optional selection of still image capture or videocapture, and (v) LED light intensity. Then, after scrolling to select asubsystem, the physician can actuate the central up/down actuator 410 toadjust an operating parameter of the selected subsystem. As will bedescribed further below, the selection of subsystems as well as thereal-time operating parameters of each subsystem will be displayed on avideo monitor or display 112 as shown in FIG. 1 . Thus, it can beunderstood that the physician may operate the scrolling button 406 toscroll through and select any subsystem or feature while observing suchas selection on the display 112, and then actuate the up/down actuator410 to adjust an operating parameter, which also can be observed on thedisplay 112.

In another aspect of the invention, the controller 110A includes acontrol algorithm for operating the control pad 122, which provides ajump back to a default condition after the scroll button or actuator 406has been used by the physician. For example, the default condition willbe a selected default subsystem, which is actuatable by the centralup/down actuator 410. In one variation, the default subsystem is thefluid inflow/outflow rate, which may be the subsystem most commonlyactuated by the physician to control fluid flow into and out of aworking space. As described above, the physician may use the scrollingbutton 406 to select any subsystem for adjustment of an operatingparameter. If, however, the physician does not continue to scrollbetween the various subsystems or change a parameter within apredetermined time interval, then the control algorithm will jump backto the default subsystem, which may be the fluid inflow/outflow rate.The predetermined time interval, or timeout, for the control algorithmto jump back to the default condition may be anywhere from 1 second to10 seconds, more often between 2 seconds and 5 seconds.

Still referring to FIG. 6 , the assembly of the handle component 120with endoscope component 125 is shown with a plane P to illustrate thesterile field 415 and the non-sterile field 420 relative to theendoscope assembly. As can be understood, the disposable endoscopecomponent 125 is sterilized and the physician or nurse would remove thecomponent 125 from sterile packaging, which would then define a sterilefield 415. The endoscope component 125 then would be mated with thehandle component 120, which defines the non-sterile field 420. In othervariations (not shown), a plastic film or other plastic housing couldcover the handle portion 120.

A method of the invention can also be understood from FIG. 6 . It can beunderstood that the physician must insert the tool 188 into the workingchannel 170 in a manner that would ensure the sterility of the tool. Ascan be seen in FIG. 6 , the grip 152, which is sterile has a largediameter recess R therein, which tapers into the proximal port 172 ofthe working channel 170. In one variation, the diameter of the recess Ris at least 15 mm and often greater than 20 mm. The depth of the recesscan range from 5 mm to 20 mm or more. Thus, it can be understood thatthe physician can easily insert the distal end 425 of a tool 188 intothe mouth of the large diameter recess R without any risk of contactingthe non-sterile handle portion 120. Thereafter, the physician can movethe tool distal end 425 distally over the surface 428 of the recess Rand into and through the port 172 of the working channel 170. By usingthis method, the physician can be assured that the tool 188 will notcontact the non-sterile field 420.

Now turning to FIG. 9 , another aspect of the invention is shown, whichrelates to electronic mechanisms carried by the endoscope 500 forre-orienting the image on the display in response to rotation of theendoscope shaft 510 to ultimately provide an image-upright configurationon the display. In one variation, an accelerometer 515 (which cancomprise an accelerometer gyroscope combination) is provided, which cansend signals to a controller and image processor related to rotation ofthe endoscope shaft 510. For example, an STmicro IIS2DH 3-axisaccelerometer can be used or a 6-axis IMU (Inertial Motion Unit) with 3accelerometers and 3 gyroscope axis such as an STmicro ISM330DLC can beused.

The image processor in the controller then can use the accelerometersignals to calculate a necessary amount of rotational correction for theimage re-orientation. The calculation includes the degree of rotation ofthe shaft 510 relative to the longitudinal axis 518 of the shaft 510.The image is then electronically rotated to display on any video displayor monitor can be carried by the handle of the device or most often is aremote display. Thus, the video image on the display can at all times bein an image-upright configuration for viewing by the physician.

As can be seen in FIG. 9 , the accelerometer 515 is carried on theproximal spool 285, which is rotatable within the handle assembly 520.Thus, any rotation of the rotating component 522 independent of thehandle 524 or rotation of the handle 524 relative to the longitudinalaxis 518 of the shaft will be sensed by the accelerometer 515 to thusallow re-orientation of the image on the display. In the variation ofFIG. 9 , a second accelerometer 540 is carried on the circuit board 545,which is fixed in the non-rotating handle 524. Thus, signals from thisaccelerometer 540 provide signals of rotation of the handle only. In onevariation, signals from both accelerometers 515, 540 can be compared todetermine rotation of the rotating component relative to the handle 524.In one aspect, signals from the second accelerometer 540 can be used ifsignals from the first accelerometer 515 fail for any reason. An alerton the display can indicate to the user if either the first or secondaccelerometer has failed to perform properly.

FIGS. 10 and 11 illustrate another variation of an endoscope working end550, which is similar to the previous embodiment. The thin-wall outersleeve 552 is in phantom view in FIG. 10 and the thin-wall workingchannel sleeve 554 is shown. As described previously, electronic signalsfrom the image sensor 555 (FIG. 11 ) as well as power for the imagesensor and LEDs 558A and 558B are carried in a flex circuit 560extending through the shaft 510 of the endoscope. Since the endoscopeshaft 510 will be operating in a fluid environment, it has been foundthat significant RF shielding is needed around the signal-carryingelectrical conductors in the flex circuit 560 to ensure that potentialelectrical devices introduced through the working channel 564 will notgenerate electrical fields that may interfere with signals carried inthe flex circuit 560.

Thus, in one variation shown in FIG. 10 , the flex circuit may be anedge-coupled stripline design where two outer dielectric layers 562 aand 562 b carry electrical conductors 565 (including ground planes) andare configured to function as a shield relative to the electricconductors 570 disposed in a middle layer 572 between the two outerlayers 562 a and 562 b. In this variation, the plurality of electricconductors 570 disposed in the middle layer 572 are adapted to carry allthe signals from the image sensor 555. Thus, the two outer layers 562 aand 562 b function as a shield to prevent any potential interferencefrom electrical tools that might interfere with the signals carried bythe interior conductors 570 in the middle layer 572.

In one variation, the signal carrying conductors 570 in the middle layer572 are provided with a dielectric insulator layer on both sides thathas a thickness of at least 0.0005″, at least 0.001″ or at least 0.002″.The insulator layers can be any suitable power material such Kapton.

In some variations, the number of electrical conductors 570 that carryimage signals in the middle layer 772 can vary from 4 to 24 or more andtypically range from 12 to 20 conductors. In this variation, theelectrical leads to the LEDs 558A and 558B are also carried in themiddle layer 572, which could be subject to interference from theelectrical tool. Thus, providing the electrical leads and signalconductors in the middle layer 572 in the stripline design allows for anoverall flex circuit 560 that is thinner and more flexible than otherconfigurations that provide adequate RF shielding.

Now turning to FIGS. 11-13 , the endoscope shaft working end 550 issimilar to that of FIGS. 7A and 7B. In the variation of FIG. 11 , theshaft working 550 end has a secondary flexible hinge portion 580, whichallows for changing the angle of the field of view FOV of the imagesensor 555 about its axis 574. For introduction into a working site inthe patient's body, the working end 550 of the shaft 510 has a distalsegment 585 that has an axis 588 that is angled relative to thelongitudinal axis 518 of the shaft 510 at a selected angle, which can befrom 5° to 30°. It can be seen in FIG. 11 that a second or intermediatesegment 595 of the working end 550 includes a living hinge portion 580,which allows it to flex relative to the proximal shaft segment 600. Theintermediate segment 595 and distal segment 585 are fixed together at anangle, which can be seen in FIGS. 11 and 12A. The mechanism foractuating the distal segment 585 and intermediate segment 595 to aflexed position (see FIG. 12B) consists of inserting an elongated toolbody or shaft 604 through the working channel 564 as describedpreviously.

FIGS. 12A and 12B are schematic transparent views of the working end 550of FIG. 11 showing the interior working channel 564 and the proximalshaft segment 600, the intermediate shaft segment 595 and the distalshaft segment 585. In FIG. 12 B, it can be seen that the elongated toolbody 604 (phantom view) has been inserted through the working channel564, which causes multiple effects. First, as described previously, theelongated tool shaft 604 stretches the resilient silicone sleeve 610around the working end 550 (FIG. 11 ) to expand the working channel 564from a collapsed condition to an expanded condition. At the same time,the introduction of the tool shaft 604 through the working channel 564flexes the proximal hinge 580 at the proximal end of the intermediatesegment 595 to cause the intermediate and distal segments 595 and 585 toflex away from the repose position (FIG. 12A) to a tensioned position(FIG. 12B) wherein the axis 588 of the image sensor 555 is parallel tothe longitudinal axis 518 of the proximal shaft portion 600. In thisflexed position of FIG. 12B, the image sensor 555 then is aligned withthe longitudinal axis 518 of the shaft and the sensor axis 574 and theangle of the field of view FOV then can be 0° relative to thelongitudinal axis 518 of the shaft.

In this variation shown in FIG. 11 , it can be seen that the tensioningsupport sleeve 625 is shown, which partially surrounds the proximalendoscope shaft portion 600 and sleeve segment 595. More in particular,the support sleeve 625 has an upper surface 628 that is fixed to theadjacent upper surface 630 of the proximal shaft portion 600. Thesupport sleeve 625 has a longitudinal discontinuity 626 therein and thesleeve extends around the shaft from about 200° to 360°. It can furtherbe seen in FIG. 11 that the support sleeve with a length LL, whichextends over a portion of the proximal shaft 600 and over a portion ofthe intermediate sleeve 595. As can be seen in FIGS. 11 and 13 , theinterior portion of the support sleeve 625 has the longitudinal gap ordiscontinuity 626, which allows the side portions 640 a and 640 b to beflexed outwardly when an elongated tool shaft 604 is introduced throughthe working channel 564. In this aspect, the support sleeve 625functions as a spring, which urges the side portions 640 a and 640 bradially inwardly to return the endoscope shaft 510 to a straightconfiguration when the tool shaft 604 is removed from the workingchannel 564.

In another aspect of the invention referring to the exploded view ofFIG. 13 , it can be seen that the distal end of the distal shaft segment585 includes a housing 650 that carries both the image sensor 555 andfirst and second LEDs 558A and 558B. The housing 650 can be molded outof any suitable polymer and includes means for providing flex circuitconnections to both the image sensor 550 and the LEDs. An upper guidesurface 655 is coupled to the sensor housing 650 to provide a slidinginterface against, which the tool shaft 604 can push and deflect thedistal segment 585 and sensor housing 650. A lower guide surface 660 iscoupled by a flexible element 664 to the working channel sleeve 554 toprovide a sliding interface against, which the tool shaft 604 can openthe working channel 564 without contacting the silicone sleeve 610 (seeFIG. 11 ).

Although particular embodiments of the present invention have beendescribed above in detail, it will be understood that this descriptionis merely for purposes of illustration and the above description of theinvention is not exhaustive. Specific features of the invention areshown in some drawings and not in others, and this is for convenienceonly and any feature may be combined with another in accordance with theinvention. A number of variations and alternatives will be apparent toone having ordinary skills in the art. Such alternatives and variationsare intended to be included within the scope of the claims. Particularfeatures that are presented in dependent claims can be combined and fallwithin the scope of the invention. The invention also encompassesembodiments as if dependent claims were alternatively written in amultiple dependent claim format with reference to other independentclaims.

Other variations are within the spirit of the present invention. Thus,while the invention is susceptible to various modifications andalternative constructions, certain illustrated embodiments thereof areshown in the drawings and have been described above in detail. It shouldbe understood, however, that there is no intention to limit theinvention to the specific form or forms disclosed, but on the contrary,the intention is to cover all modifications, alternative constructions,and equivalents falling within the spirit and scope of the invention, asdefined in the appended claims.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. The term “connected” is to beconstrued as partly or wholly contained within, attached to, or joinedtogether, even if there is something intervening. Recitation of rangesof values herein are merely intended to serve as a shorthand method ofreferring individually to each separate value falling within the range,unless otherwise indicated herein, and each separate value isincorporated into the specification as if it were individually recitedherein. All methods described herein can be performed in any suitableorder unless otherwise indicated herein or otherwise clearlycontradicted by context. The use of any and all examples, or exemplarylanguage (e.g., “such as”) provided herein, is intended merely to betterilluminate embodiments of the invention and does not pose a limitationon the scope of the invention unless otherwise claimed. No language inthe specification should be construed as indicating any non-claimedelement as essential to the practice of the invention.

All references, including publications, patent applications, andpatents, cited herein are hereby incorporated by reference to the sameextent as if each reference were individually and specifically indicatedto be incorporated by reference and were set forth in its entiretyherein.

What is claimed is:
 1. An endoscope electrically coupled to an image display and configured for use with an elongated tool, the endoscope comprising: an elongated shaft having a shaft assembly located at a proximal end of the elongated shaft, an image sensor and a lens facing distally at a distal end of the elongated shaft; a handle coupled to the shaft assembly, where the shaft assembly is rotatable in the handle; a working channel extending through the elongated shaft and having a proximal channel portion and a distal channel portion, the proximal channel portion having a central axis and a first cross section, the distal channel portion having a second reduced cross-section in a first position; wherein the distal channel portion is expandable such that advancement of the elongated tool therein expands the distal channel portion about the central axis into a second position which permits advancement of a portion of the elongated tool out of the distal channel portion while the portion remains in alignment with the central axis, wherein the distal channel portion comprises a first sidewall cut-out and a second sidewall cut-out which permits the distal channel portion to flex outwardly to the second position; a support sleeve located about a portion of the distal channel portion, the support sleeve configured to flex outwardly with the distal channel portion, wherein the support sleeve urges the distal channel portion inward upon removal of the elongated tool; a flexible hinge extending along the distal channel portion; a first accelerometer coupled to the elongated shaft such that rotation of the elongated shaft rotates the first accelerometer and the elongated shaft, wherein the first accelerometer is configured to provide signals to determine rotation of the image sensor relative to a longitudinal axis of the elongated shaft, wherein the signals permit rotation of an image on the image display; and a lower guide surface adjacent to the support sleeve of the distal channel portion, wherein the lower guide surface provides a sliding interface against which the elongated tool can advance through the distal end without contacting the support sleeve.
 2. The endoscope of claim 1, further comprising a second accelerometer located within the handle wherein when in the first position the image sensor has a 0 to 15 degree viewing angle relative to the central axis.
 3. The endoscope of claim 1, further comprising a flex circuit having a plurality of electrical conductors which are configured to transmit power and image signals to and from the image sensor, the flex circuit including outer dielectric layers that are configured to shield the plurality of electrical conductors from electrical interference.
 4. The endoscope of claim 1, wherein the support sleeve comprises an elongated discontinuity extending along a length of the support sleeve.
 5. The endoscope of claim 1, wherein the flexible hinge is located at an intermediate segment that is adjacent to the distal end, wherein insertion of the elongated tool causes the distal end of the elongated shaft to displace the support sleeve radially away from the central axis.
 6. The endoscope of claim 1, further comprising a housing configured to carry the image sensor and at least one light emitting diode.
 7. The endoscope of claim 6, further comprising an upper guide surface adjacent to the housing, wherein advancement of the elongated shaft distally beyond the working channel causes the elongated tool to push against the upper guide surface moving the distal channel portion into the second position.
 8. An endoscope comprising: an elongated shaft extending about a central axis to a distal end carrying an image sensor at a distal end of the elongated shaft; an distal segment adjacent to the distal end of the elongated shaft, wherein the distal segment comprises a first sidewall cut-out and a second sidewall cut-out; a working channel within the elongated shaft and having a proximal channel portion and a distal channel portion in an angled position with respect to the central axis, wherein the distal channel portion extends through the distal segment of the elongated shaft, wherein in the angled position the distal channel portion comprises a first cross-sectional area that smaller than a cross-sectional area of the proximal channel portion; a flexible hinge extending along the working channel and located between the distal channel portion and proximal channel portion; wherein the first sidewall cut-out and the second sidewall cut-out permit the distal segment to flex outwardly when an elongated tool shaft is advanced through the working channel and wherein passage of the elongated tool shaft through the distal channel portion causes the distal segment of the elongated shaft to flex outwardly to move the distal channel portion from the angled position to a second position having to permit a portion of the elongated tool shaft to advance out of the distal channel portion in alignment with the central axis of the working channel; a support sleeve located about a portion of the distal segment, the support sleeve urges the distal segment inward upon removal of the elongated tool shaft, a housing configured to carry the image sensor and at least one light emitting diode; and a lower guide surface coupled to a sleeve of the working channel, wherein the lower guide surface provides a sliding interface against which the elongated tool shaft can advance through the distal segment without contacting the support sleeve.
 9. The endoscope of claim 8, wherein the support sleeve comprises an elongated discontinuity extending along a length of the support sleeve.
 10. The endoscope of claim 8, wherein the flexible hinge is located at an intermediate segment that is adjacent to the distal segment, wherein insertion of the elongated tool shaft causes the distal end of the elongated shaft to displace radially away from the central axis.
 11. The endoscope of claim 8, further comprising an upper guide surface coupled to the housing, wherein advancement of the elongated tool shaft distally beyond the working channel causes the elongated tool shaft to push against the upper guide surface to deflect the housing. 